One of the worst types of structural damage that can befall a building is roof damage. The devastation caused by high winds, hurricanes, tornadoes and the like is depicted by the media, often by focusing on the damage done to homes, especially to the roofs of those homes. In these cases, damage to the roof often leads to tremendous damage to the rest of the building, as a result of structural damage, and damage caused by the elements, such as rain or snow.
The roof of a building serves a number of purposes. First, it protects the interior of the building from the elements, such as rain, snow and hail. It also serves as an important structural component of the building, often linking the walls together, and adding strength to the building.
Wind causes several different types of damage to a roof. First, the wind, when blowing in a certain direction, can flow between the roof covering and the underlying substrate. This air flow can cause the roof covering to peel up and lift itself off the roof. The removal of the roof covering leaves the exposed roof susceptible to water, which can now enter through the area that is no longer protected by the missing covering. A second type of damage is caused by the effect of high speed attached flow over the surface of the roof. The deflection of the flow over the roof line squeezes the streamlines closer together, accelerating the speed and lowering the static pressure in accordance with Bernoulli's principle. This causes uplift on part or all of the roof structure, thereby exerting an upward force on the roof. This force not only causes the roof covering to lift from the roof, but can also cause the roof to pull away from the joists to which it is attached.
Various attempts have been made to reduce the destructive effect of hurricane force winds on a roof, including various types of roof spoilers or wind deflectors. For example, various types of roof wind spoilers have been disclosed, for example, in U.S. Pat. No. 2,206,040, U.S. Pat. No. 2,270,537, U.S. Pat. No. 2,270,538, U.S. Pat. No. 6,601,348, and U.S. Patent Application Publication 2006/0248810. Most of these spoilers are attached directly onto the roof surface. To achieve their goal, most employ a member that, when deployed, is orthogonally disposed to the roof surface. This member may be either permanently disposed, or manually or automatically disposed only when needed. Other publications, for example U.S. Pat. No. 6,601,348, and U.S. Patent Application Publication 2007/0113489, disclose a spoiler that can be attached to the fascia, rather than the roof surface. As the air flow travels along the surface of the roof, this vertical barrier presents an obstacle to its continued flow. As a result, the wind must travel over the barrier, which causes the air flow to become turbulent. In fact, the air flow directly at the roof may reverse directions, thereby pushing the roof covering down. The turbulent nature of the air flow created by these spoilers significantly decreases the negative pressure area described above. FIG. 1a shows the flow of air over a typical roof. Note the attached flow as the wind moves over the roof surface. FIG. 1b shows the resulting air flow when a roof spoiler is installed on the roof. Note the turbulence created downwind of the spoiler. Also of interest is the change in the direction of the wind along the roof surface.
Up to now, no roof spoilers have enjoyed commercial success or gained widespread use. This lack of success is probably due to a number of reasons, including unattractive appearance (e.g., due to poor aesthetic design or location on roof surface), poor performance (e.g., due to product design, operation or location), costs, complexity of installation, etc.
Therefore, it is an object of the present invention to provide a roof spoiler device that creates a turbulent air flow on the roof surface to prevent wind damage. It is an additional object to provide a device that reduces the flow of air under the roof covering. It is a further object to provide a roof spoiler device that has an acceptable aesthetic appearance. It is also an object to provide a roof spoiler device that may be used in conjunction with a roof gutter.